1. Field of the Invention
The present invention relates to a flow control valve, and more particularly, to a new flow control valve designed to control a flux of the fluid in response to the frequency of an input pulse.
2. Description of the Prior Art
Flow control valves designed to control a flux of the fluid in response to an electric signal have heretofore been known. However, such conventional types of flow control valves were generally so constructed that initially a sawtooth-wave-form pulse signal and a variable reference level pulse signal are both sent to a comparator circuit and then the valve is opened when the level of said sawtooth-wave-form pulse signal is larger than that of a reference level pulse signal. That is, these types of flow control valves are generally to control the flux of fluid by a so-called pulse width modulation system.
Consequently, in such conventional flow control valves, an electric circuit was especially sophisticated, while their responsive performances and controllable accuracies were not always satisfactory for users because of structural limitations of the valve body to be used.